RE: [RFC PATCH] build: reduce use of AVX compiler flags

["Varghese, Vipin" <Vipin.Varghese@amd.com>]

[Public]

Snipped

> > > > When doing a build for a target that already has the instruction
> > > > sets for AVX2/AVX512 enabled, skip emitting the AVX compiler
> > > > flags, or the
> > > > skylake-avx512 '-march' flags, as they are unnecessary. Instead,
> > > > when the default flags produce the desired output, just use them
> > > unmodified.
> > > >
> > > > Depends-on: series-34915 ("remove component-specific logic for AVX
> > > builds")
> > > >
> > > > Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

Hi Bruce,

From AMD end we have tested with gcc 12, and 13.
We tried cross checking with and without patch for libraries such as `librte_net_ice and librte_net_i40e`.

We did not find much changes in the assembly code generated.
I hope this is expected? Can you please share any pointers?\

> > > > ---
> > > >
> > > > This patchset depends on the previous AVX rework. However, sending
> > > > it separately as a new RFC because it effectively increases the
> > > > minimum compiler versions needed for x86 builds - from GCC 5 to 6,
> > > > and Clang 3.6 to 3.9.
> > > >
> > > > For now, I've just documented that as an additional note in the
> > > > GSG
> > > that
> > > > these versions are recommended, but it would be simpler if we
> > > > could
> > > just
> > > > set them as the required minimum baseline (at least in the docs).
> > > >
> > > > Feedback on these compiler version requirements welcome.
> > > >
> > >
> > > +techboard
> > >
> > > Ping for a little bit of feedback for this. Are we ok to bump the
> > > minimum compiler versions as described above, or will I continue
> > > with the approach in this RFC of keeping the minimum and just
> > > recommending the higher versions for x86 platforms?
> > >
> > > For reference GCC 6.1 was released April 2016[1], and, Clang 3.9 was
> > > released Sept 2016[2]
> > >
> > > /Bruce